In treating ligamentous strains of any joint of the body such as, for example, the articular facet joints of the vertebrae and costovertebral joints between the ribs and the vertebrae, it is important that the treatment be localized to the specific area or joint that is injured to avoid straining adjacent vertebral segments or joints. In treatment of these joints, the direction and pressure applied must be specific and must be maintained with sufficient force until a release occurs, usually within minutes. Forces extended for a long period of time past the time of release are generally of no benefit and can be counterproductive. The articular facet joints of the vertebrae and costovertebral joints between the ribs and the vertebrae lend themselves to correction by maintaining a specifically directed pressure (a vector force). In treating the articular facet joints, a vector force directed anteriorly, towards the front of the body, and superiorly, towards the head, and generally in a direction along the plane of the facet joint provides favorable treatment. In treating a costovertebral joint, a vector force anteriorly, superiorly, and laterally applied to the angle of the rib achieves a favorable result.
Previously developed techniques for treating strains of spinal joints have included the use of traction devices in which traction forces are applied along the entire spine or entire regions of the spine. However, when such traction is applied, normal segments of the spine as well as abnormal segments receive traction. The abnormal areas are surrounded by paravertebral muscle spasm guarding them from motion. The normal segments are not surrounded by muscle spasm and therefore, when traction is applied to normal as well as abnormal areas, the normal areas are the first and usually only areas to move. When this movement occurs, the proprioceptive nerve fibers from these previously normal joints reflexly set up muscle spasm surrounding these joints. This creates secondary problems while not resolving the primary problem for which traction was prescribed. An additional problem noted with linear or tensil traction is that the vector force is not applied along the planes of the joints involved which is required to achieve a release.
A need has thus arisen for a device for the treatment of strains of joints of the body, and particularly joints of the vertebrae and ribs which allows for sustained localized treatment and for the generation of a more favorable vector force applied to the joint.